1. Field of the Invention
The present invention relates to a fluid control valve and fluid supply/exhaust system. In greater detail, the present invention refers to a fluid control valve, and a fluid supply/exhaust system, in which a member "a" is made unitary with a rod shaped shaft which applies pressure to a valve holder and is moved upwardly and downwardly by a coil using electromagnetic induction, and thereby, the portion between the valve seat and the valve holder is opened and closed. The fluid control valve and fluid supply/exhaust system of the present invention is chiefly used in semiconductor manufacturing apparatuses.
2. Description of the Related art
Conventionally, fluid control valves which controlled fluids flowing through the valve body by means of opening and closing a portion between a valve body by means of opening and closing a portion between a valve seat and a valve holder using a drive unit and valve holders comprising a diaphragm and a diaphragm holder, and were of the following types:
One type having a rotating mechanism unit which is manually operated, in which a valve rod is moved upwardly and downwardly using the rotational movement of the rotating mechanism unit, and the portion between the valve seat and the diaphragm is opened and closed (hereinbelow, this type of fluid control valve is referred to as a manual valve (not shown in the figures));
A second type having a gas filling and discharge mechanism, in which the valve rod is moved upwardly and downwardly using a difference in pressure in this gas, and the portion between the valve seat and the diaphragm is opened and closed (hereinbelow, this type of fluid control valve is referred to as an air pressure valve, (FIG. 4)); and
A third type having a mechanism which is subject to electromagnetic induction using a coil, wherein an iron core and plunger are installed at separate locations using this mechanism, and in concert with this, a bubble disc affixed to a plunger is moved upwardly and downwardly, and a portion between the bubble disk and a valve seat is opened and closed (hereinbelow, this type of fluid control valve is referred to as an electromagnetic valve (FIG. 5)).
Hereinbelow, the method of opening and closing the valve in electromagnetic valves and air pressure valves, which are referred to as automatic valves, will be explained.
FIG. 4 is a schematic cross sectional view of an air pressure valve of a type in which the open and closed state of the valve is normally closed; the state is depicted in which the valve is closed. The opening and closing operation of the value is given below.